Brazing of aluminium and aluminium to steel

The chapter focuses on the problems of reactive-flux brazing and soldering of aluminium and aluminium to steel. High-temperature fluxes of the K,Al,Si/F salt system improve wetting and capillary properties of filler metals during brazing. The possibility of brazing aluminium using a reactive flux without a filler metal is established. Brazed joints on aluminium have strength equal to that of the base metal, and joints between aluminium and steel preserve their performance after thermal cycling tests. Reactive fluxes can be used for furnace, induction and arc brazing. Low-temperature fluxes based on polyatomic alcohols, which contain synthesised complex tetrafluoroborates of metals with nitrogen-bearing bases, improve conditions for formation of brazed joints on aluminium.